Gold futures rose for the third time in four sessions as mounting tension over Ukraine boosted demand for haven assets. Silver futures for September delivery rose 0.6 percent to $21.012 an ounce on the Comex. Aluminum entered a bull market in London and traded near the highest in 16 months on speculation demand will exceed supply for the metal used in everything from cars to packaging. West Texas Intermediate traded near the highest price in three weeks before stockpile data that may signal the strength of fuel demand in the U.S., the world’s biggest oil consumer. Natural gas futures slipped in New York to the lowest price in more than seven months as meteorologists predicted mild weather.